Medical instrument with probe and methods of using the same

ABSTRACT

A medical instrument including a probe adapted to be inserted into an orifice of an animal&#39;s body. Electromagnetic radiation is sensed by a sensor mounted on the probe. The sensor can then determine, by variations in the amount of radiation received, whether the walls of the body orifice block the radiation, thereby indicating a position of the sensor, and thus, the probe, within the orifice.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of, and claims priority to andthe benefit of, U.S. patent application Ser. No. 13/743,733, filed Jan.17, 2013 entitled “MEDICAL INSTRUMENT WITH PROBE AND METHODS OF USINGTHE SAME”, which in turn is a continuation of, and claims priority toand the benefit of, U.S. patent application Ser. No. 12/649,595, filedDec. 30, 2009, now U.S. Pat. No. 8,374,683, entitled “MEDICAL INSTRUMENTWITH PROBE, PROBE COVER, AND METHODS OF USING THE SAME”, each of whichis hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates a medical instrument with a probe adaptedto be inserted into an orifice in an animal's body, such as an animal'sear. In one aspect of the invention the medical instrument includes asystem for determining the status of a probe cover adapted to be mountedover the probe, and in another aspect, the invention relates to a systemfor determining the depth of insertion of the probe into the orifice.

BACKGROUND OF THE INVENTION

Medical instruments are often inserted into body orifices in order toexamine the condition of internal body tissue and other body conditions,to apply medicines, and for other purposes. Typically, such medicalinstruments include a probe having a generally conical peripheralconfiguration that is inserted into the orifice and that usually isseated against the walls of the orifice. Such medical instrumentsinclude ear instruments such as, for example, otoscopes for examining apatient's ear, infrared thermometers for measuring the temperature of anear drum, and tympanometers.

Medical instruments that are adapted to be inserted into a body orificeare usually expensive and must be reused. The probe section of themedical instrument that is adapted to be inserted into the orifice maybe contaminated with body fluids, wax, hair, and skin cells. By reusingthe medical instrument, such contaminates may be transmitted to otherpatients, which naturally may result in the transmission of disease orother undesirable effects. In order to provide for sanitary reuse ofsuch medical instruments, disposable probe covers have been utilized.Such probe covers are typically hollow and usually possess aconfiguration conforming to that of the associated probe. Probe coversmay be selectively mounted to the medical instrument, in a positionmounted over and around the probe, such as by a compressive snap fit orby a threadable connection. After using the medical instrument with theprobe cover in connection with one patient, the probe cover is detachedfrom the medical instrument and permanently discarded. A new probe coveris then mounted over the probe and selectively attached to the medicalinstrument before the medical instrument is reused with another patient.

Sometimes a healthcare practitioner may incorrectly presume that a probecover mounted on the medical instrument is a fresh probe cover ratherthan one that has already been used. In such event, the probe cover maytransmit contaminants to the next patient on which the medicalinstrument is used. Aspects of the present invention were developed inresponse to concerns about cross-contamination due to errant reuse of aprobe cover.

Another aspect of the present invention is directed to determining adepth of insertion of the probe and probe cover, and preferably whetherthe probe and probe cover have achieved a minimal or preferred depth ofinsertion when inserted into a body orifice, such as an ear. In thisregard, aspects of the current invention augment the teachings disclosedin Applicant's co-pending U.S. Ser. No. 12/610,760 entitled “THERMOMETERFOR DETERMINING THE TEMPERATURE OF AN ANIMAL'S EAR DRUM AND METHOD OFUSING SAME”, filed Nov. 2, 2009, now U.S. Pat. No. 8,306,774, thedisclosure of which is hereby incorporated by reference.

In order to perform some procedures, the medical instrument will notproperly function unless the probe is inserted to a sufficient depth, oran ideal depth, into a body orifice. Therefore, it is important todetermine the depth of insertion of the probe and any probe cover as amedical instrument is being used, in order to insure that the medicalinstrument is accomplishing its intended purpose. For example, asexplained in more detail in the previously mentioned co-pending patentapplication, when measuring the temperature of an animal's ear drumbased upon the infrared radiation emitted by the ear drum, it isimportant that the probe be inserted sufficiently into the ear so thatessentially only infrared radiation emitted by the region around the eardrum is registered. If the probe is not sufficiently inserted into theear, then the infrared thermometer will receive infrared radiation fromother areas of the ear canal and the outer ear that do not accuratelyindicate the temperature of the ear drum. The medical instrument of thepresent invention may also be used to determine the depth of insertionof the probe and any probe cover.

SUMMARY OF THE INVENTION

The present invention relates to the medical instrument including aprobe adapted to be inserted into an orifice of an animal's body. Theinstrument includes an emitter of electromagnetic radiation that issensed by a sensor mounted on the probe. The sensor can then determine,by variations in the amount of radiation received from the emitter,whether a probe cover is mounted over the probe. A sensor can also beused to determine the extent to which the walls of the body orificeblock the radiation received from the emitter, thereby indicating theposition of the sensor, and thus, the position of the probe within theorifice. A special probe cover is disclosed, and methods of using themedical instrument are also disclosed.

In one embodiment, the probe cover is fashioned of a material, treatedwith a coating, or otherwise designed to partially transmit radiationwithin a selected bandwidth. The bandwidth of partial transmittance maybe selected to be within, coincide with, or overlap a bandwidth ofrelatively intense radiation emitted by the emitter.

In other embodiments, the invention includes a microprocessor with atimer that is programmed either to generate a signal or to disable theinstrument if a minimum time interval has passed since the probe coverwas mounted over the probe and the sensor has not sensed the removal ofthe probe cover. If the system detects that the probe cover has beeninserted into a body orifice by blockage of the radiation sensed by thesensor, then the microprocessor may be programmed either to generate asignal or to disable the instrument if a minimum time interval haspassed since the insertion and the sensor has not sensed the removal ofthe probe cover.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanyingdrawings, wherein:

FIG. 1 is a schematic side view of an otoscope in connection with whichthe present invention may be used;

FIGS. 2A and 2B are a schematic side view, and a schematic perspectiveview, respectively, of a probe cover that may be used in connection withthe present invention;

FIG. 3 is a schematic illustration of a probe in the otoscope shown onFIG. 1 in which an emitter of radiation is mounted on the head sectionof the otoscope, a sensor is mounted on the probe of the otoscope, and aprobe cover as shown in FIGS. 2A and 2B may be attached and detachedfrom the otoscope in the directions shown by the indicated arrows;

FIG. 4 is a schematic illustration of the probe and attached probe covershown in FIG. 3 inserted into a human's ear canal;

FIG. 5 is a schematic illustration of a side view of a probe on which asensor according to one embodiment of the present invention is mounted;

FIG. 6 is a schematic illustration of a side view of a probe on whichanother sensor in accordance with another embodiment of the presentinvention is mounted;

FIG. 7 is a schematic illustration of a side view of a probe on whichanother sensor in accordance with yet another embodiment of the presentinvention is mounted; and

FIG. 8 is a block diagram of electrical interconnections between variouscomponents of the medical instrument in accordance with an embodiment ofthe present invention.

DESCRIPTION OF A PREFERRED EMBODIMENT

The present invention will be described with reference to theaccompanying drawings wherein like reference numerals refer to the sameitem. It should be appreciated that the following description isintended to be exemplary only, and the scope of the invention envisionsother variations and modifications of these particular exemplaryembodiments.

There shown in FIG. 1, in general illustration, a conventional otoscope10 that may be useful in connection with the present invention. Anotoscope is a device used to examine and inspect the inner ear of ahuman or other animal. Although in an exemplary embodiment, reference ismade to an otoscope, it should be appreciated other medical instruments,such as an infrared thermometer having a probe adapted to being insertedinto a human ear, also may be advantageously employed in connection withthe present invention.

The otoscope 10 includes a handle 12, a neck 14, a head section 16, anda probe 18. The neck 14 connects the head section 16 with the handle 12.Preferably, the neck 14 is constructed so that the head section 16 maybe selectively rotated with respect to the handle 12 and may beselectively locked into a desired position of rotation by means of aclamping screw 20. The probe 18 generally possesses a hollow interiorand both an interior and external frusto-conical configuration. Theprobe 18 may be attached permanently or removably from a supportstructure such as, for example, the head section 16.

The otoscope 10 typically has a viewing lens system and a lightillumination source disposed in the head section 16. The light sourceprojects light through the interior of the probe 18, and illuminates theear and ear canal. The handle section 12 may house batteries that areused to power the light source. A healthcare practitioner looks throughthe lens system, through the interior of the probe 18, and to theilluminated area of the ear and ear canal.

It will be appreciated that direct contact of the probe 18 with the wallof the ear and ear canal will result in ear wax or otiler residueaccumulating on the periphery of the probe 18. Reusing the same probe 18may transmit such ear wax and other residue to another patient, whichmay result in the transmission of disease or other adverse effect. Theprobe 18 may be cleaned and sanitized, however, errors may occur byforgetting the cleaning step, or by achieving only incompletesanitation. Moreover, patients may be reluctant to believe that theprobe 18 has been sufficiently sanitized, and therefore may be reluctantto allow the healthcare practitioner to insert the probe 18 into theirears.

In recognition of these sanitation concerns, disposable probe covers aremounted over the probe 18 and are removably attached to the head section16. An exemplary probe cover 22 is shown in FIGS. 2 and 2B. The probecover 22 is fashioned as a hollow tube. Typically, a probe cover 22possesses a generally uniform thickness, so that the exterior surfacepossesses a configuration that is generally similar to the interiorsurface of the probe cover 22. The probe cover 22 may be removablyattached to the head section 16 of the otoscope 10 such as through asnap-fit connection or through a threadable connection. The probe cover22 shown in FIGS. 2A and 2B possesses a series of internal threads sothat the probe cover 22 is threadably, realeasably secured to the headsection 16. For this purpose, the probe cover 22 possesses a pair ofopposing fins 24, 26 by which a healthcare practitioner may manuallygrasp and rotate the probe cover 22. The probe cover 22 is designed forone-time use, and is intended to be disposed in the trash after use on apatient.

FIG. 4 illustrates how the probe cover 22 is typically inserted into ahuman's ear, and helps to highlight how ear wax and other residue maycome into contact with the probe cover 22 and may be carried by theprobe cover 22 after removal of the probe cover 22 from the ear.

Since probe covers are disposable, they provide more confidence thatcontamination will not be transmitted, however, there may be errors inmaking sure that a probe cover is detached and discarded after use on apatient.

One aspect of the present invention provides a safeguard for helping toinsure that the medical instrument, such as the otoscope 10, will not bereused on a different patient with the same probe cover. As shown inFIG. 3, an emitter 28 is preferably mounted on the head section 16 ofthe otoscope 10. The emitter 28 is capable of emitting electro-magneticradiation, which is directed at least in part to a sensor 30 mounted onthe outside periphery of the probe 18. Preferably the electro-magneticradiation is different from sunlight or other ambient light that mightexist in a medical facility. The radiation need not be in the visiblespectrum, but preferably is within the visible spectrum. In a preferredembodiment, the emitter comprises a blue LED that emits visible lightintensely in a bandwidth of approximately 500-550 nanometers ofwavelength. The radiation may be emitted continuously, or in pulses.

When the probe cover 22 is mounted over and covers the probe 18, and isdetachably connected to the head section 16, radiation emitted by theemitter 28 passes, if at all, through the wall of probe cover 22 beforereaching and being detected by the sensor 30. If the probe cover wall 22is not completely transparent and not completely opaque to theradiation, the sensor 30 will be able to detect a reduction in theamount of radiation being received from the emitter 28. In order to helpdetermine that the reduction in radiation received by the sensor 30 isdue to mounting of the probe cover 22 over the probe 18, and is not dueto human fingers, paper, or another object being interposed in the pathbetween the emitter 28 and the sensor 30, the probe cover 22 may beselectively constructed with special characteristics that will helpensure that the reduction in sensed radiation is due to the mounting ofthe probe cover 22 over the probe 18. For example, it may be desirablefor the probe cover 22 to have known transmittance in the range of about40 to 60%, or about 50%, within a pre-determined bandwidth. In order toachieve such desirable transmittance, the probe cover 22 may befashioned of a particular type of translucent material and a particularthickness designed to achieve such desired transmittance. The materialforming the probe cover 22 may also be impregnated with color or othermaterial in order to achieve such transmittance. Further, either theexterior surface, the interior surface, or both, of the probe cover 22may be coated with material that affects the reflection, absorption, andultimate transmittance of radiation impinging thereon within a selectedbandwidth.

The invention contemplates that color filters such as those offered byRosco Laboratories, Inc. located in Stamford, Conn. may be employed withthe probe cover 22. Such color filters include body-colored colorfilters in which a colorant is integrated within a plastic substrate bymixing a dye into a melted resin, deep-dyed color filters in which aclear polyester sheet is passed through a heated solvent suffused with adye, and surface coated color filters in which a colored material iscoated onto a polyester film base.

The characteristics of the probe cover 22, especially any coatingsapplied to probe cover 22, may possess a unique filtering of theradiation so that only very limited bandwidth of the radiation emittedby the emitter 28 is actually received by the sensor 30. In such anembodiment, the sensor 30 could also be provided with a correspondingfilter so that the overall system will properly function only if probecovers 22 having a similar filtering characteristic are employed. Thisprocess can be used to help insure that only specific types of probecovers 22 are utilized in connection with the otoscope 10.

It will also be appreciated that when the probe cover 22 has moved awayfrom the probe 18, the sensor 30 will detect an increase in the amountof radiation emitted by emitter 28. The amount of such radiationdetected will correspond with the amount of radiation originallydetected by the sensor 30, prior to mounting the probe cover 22 onto thehead section 16 and over the probe 18.

Although the emitter 28 is shown as being mounted on the head section16, it should be appreciated that the emitter 28 may be situated at avariety of locations, and need not be mounted on the head section 16.

FIGS. 5, 6, and 7 illustrate different sensor configurations andpositions that may be utilized in connection with a preferred embodimentof the invention. As shown in FIG. 5, the sensor 30 a possesses a squareconfiguration and is situated near to the large end of the probe 18. InFIG. 6 the sensor 30 b is fashioned in the shape of an elongate stripgenerally extending in a longitudinal direction relative to the probe 18and extending from the small end thereof to approximately the mid-pointlongitudinally along the probe 18. In FIG. 7 the sensor 30 c comprisesan array of circular sensor elements mounted near the smaller end of theprobe 18. Preferably the sensors 30 a, 30 b, 30 c are oriented such thatthey directly face the emitter 28.

In use, the sensor 30 first determines whether the probe cover 22 hasbeen mounted on the head section 16. As shown in FIG. 8, the sensor 30may be operatively connected to a microprocessor 32, which may contain atimer, and which may cause a signal generator 34 to display the amountof time that has lapsed since the probe cover 22 has been mounted on thehead section 16. A healthcare practitioner operating the otoscope 10 mayrealize from the amount of time displayed that the probe cover 22probably has been used and should be discarded, or, as just aprecautionary measure, the probe cover 22 should be discarded.

The invention also contemplates that the microprocessor 32 will beprogrammed to wait a predetermined time interval, such as five seconds,after the sensor 30 first senses that the amount of radiation sensedindicates that the probe cover 22 has been mounted over the probe 18 toregister the event when the probe cover 22 has been mounted. Such a timeinterval will help insure that the probe cover 22 is not simply in theprocess of being mounted, but in fact has been mounted, over the probe18 and is attached to the head section 16. In another embodiment, themicroprocessor 32 may be programmed to register that the probe cover 22is mounted on the head section 16 only after a predetermined timeinterval, such as five seconds, continuously shows that the amount ofradiation sensed by sensor 30 corresponds with the probe cover 22 havingbeen mounted over the probe 18. As an additional feature of theinvention, the microprocessor 32 may be programmed so as to sound anaudio alarm, or to provide a blinking light signal, via the signalgenerator 34 if a predetermined time interval, such as five minutes, hasoccurred after the sensor 30 first indicates that the probe cover 22 hasbeen mounted the head section 16. The microprocessor 32 would beprogrammed not to cause such signals to be generated if the sensor 30senses an amount of radiation that indicates that the probe cover 22 hasbeen removed from the head section 16 and away from the probe 18 duringthat time interval.

The present invention contemplates that the emitter 28, such as a blueLED, might automatically provide visual illumination in a continuousmanner upon removal of the otoscope 10 from a storage housing.Alternatively, as shown in FIG. 8, a switch 36 may be used toselectively activate and deactivate the emitter 28. In such a mode ofoperation, the emitter 28 may help a healthcare practitioner find probecovers, the patient's orifice, and other objects in a dark environment.In other embodiments of the present invention, the microprocessor 32could disable the light source within the head section 16 fromprojecting light through the probe 18 unless the sensor 30 detects anamount of radiation that indicates that a probe cover 22 is not mountedon the head section 16 or has not been removed after a predeterminedtime interval. In yet another embodiment, where the medical instrumentis an infrared thermometer, the microprocessor 32 could prevent thethermometer from taking any temperature readings unless the sensor 30senses an amount of radiation that indicates a probe cover 22 is mountedon the head section 16. Similarly, the microprocessor 32 could preventthe infrared thermometer from making a temperature reading if, within apredetermined time interval after the probe cover 22 has been mountedover the probe 18, the sensor 30 does not sense an amount of radiationemitted by the emitter 28 that indicates the probe cover 22 has beenunmounted from the head section 16 and removed away from the probe 18.

It should also be appreciated that the present invention may be usefulin connection with determining the depth of insertion of the probe 18and any associated probe cover 22 into an orifice of a body. Withspecial reference to FIGS. 4, 6, and 7, if the sensor 30 b, 30 c isdisposed in the orifice near the walls of the orifice, then radiationemitted by emitter 28 will be substantially blocked or occluded fromreaching the sensor 30 b, 30 c. Such blockage or occlusion will decreasethe amount of radiation sensed by the sensor 30, which may be correlatedwith a particular depth of insertion of the small end of the probe 18 orthe probe cover 22 within the orifice. In one embodiment, there is alinear correlation between the degree of reduction of sensed radiationwith the depth of insertion. In the case of an infrared thermometer, themicroprocessor 32 may be programmed to prevent a temperature reading ifthe depth of insertion is insufficient. Also, the recognition by themicroprocessor 32 that the probe 18 and any associated probe cover 22has been inserted into the orifice may be used to prompt themicroprocessor 32 to cause the signal generator 34 to generate an audioor visual signal or to prevent re-use of the medical instrument, such asby disabling the light source in the head section 16 in an otoscope orby disabling the temperature reading function of an infraredthermometer, if a pre-determined time interval has passed and the sensor30 does not indicate that the probe cover 22 has been removed. In thisregard, the switch 36 may be a multi-position switch with including oneposition to activate or deactivate the emitter 28, and another positionto activate the insertion depth function.

While exemplary embodiments have been presented in the foregoingdescription of the invention, it should be appreciated that a vastnumber of variations within the scope of the invention may exist. Theforegoing examples are not intended to limit the nature or the scope ofthe invention in any way. Rather, the foregoing detailed descriptionprovides those skilled in the art with a foundation for implementingother exemplary embodiments of the invention.

We claim:
 1. A medical instrument including a support structure; a probeattached on said support structure, said probe possessing an outerperipheral surface and adapted to be inserted into an orifice in ananimal's body; a sensor adapted to sense electro-magnetic radiation froma source of said radiation remote from the animal's body, said sensormounted on said outer peripheral surface of said probe in a position soas to receive said radiation; and a microprocessor operatively connectedto said sensor, said microprocessor configured to monitor the magnitudeof said radiation sensed by said sensor and to evaluate the degree ofany reduction of said monitored magnitude as an indication of theinsertion of said probe into the body orifice.
 2. The medical instrumentaccording to claim 1 wherein said radiation is different from ambientradiation present in the vicinity of said medical instrument.
 3. Themedical instrument according to claim 1 wherein said radiation includesambient radiation in the vicinity of said medical instrument.
 4. Themedical instrument according to claim 1 wherein said radiation isoutside the visible spectrum.
 5. The medical instrument according toclaim 1 wherein said radiation is within the visible spectrum.
 6. Themedical instrument according to claim 1 wherein said support structureincludes a head section from which said probe projects outwardly andwherein said radiation source is mounted on said head section.
 7. Themedical instrument according to claim 1 wherein said support structureincludes a head section from which said probe projects outwardly andwherein said radiation source is remote from said head section.
 8. Themedical instrument according to claim 1 further including a materialadapted to modify the transmission characteristics of said radiationfrom said remote source prior to being sensed by said sensor, saidmaterial adapted to be disposed adjacent to said sensor.
 9. The medicalinstrument according to claim 8, wherein said material is adapted to bedisposed selectively between said remote source and said sensor.
 10. Themedical instrument according to claim 8 wherein said material is adaptedto modify said transmission characteristics by blocking a portion, butless than all, of said radiation from said remote source before beingsensed by said sensor.
 11. The medical instrument according to claim 10wherein said material is adapted to modify said transmissioncharacteristics by blocking between 40-60 percent of said radiation fromsaid remote source prior to being sensed by said sensor.
 12. The medicalinstrument according to claim 1 wherein said probe extends in alongitudinal direction, wherein said sensor extends in a elongate,substantially longitudinal direction along said outer peripheral surfaceof said probe and whereby when said probe is inserted into the orifice,said radiation is partially blocked by the walls of the orifice fromreaching said sensor and as said probe is inserted deeper into theorifice even more of said radiation is blocked by the walls of theorifice from reaching said sensor.
 13. The medical instrument accordingto claim 12 wherein said microprocessor is configured to calculate adepth of insertion of said probe into the orifice in a substantiallylinear relationship with the decrease in the magnitude of said radiationsensed by said sensor.
 14. The medical instrument according to claim 13wherein said microprocessor is further programmed to determine that apre-determined depth of insertion constitutes a preferred position ofsaid probe, wherein said medical instrument further comprises a signalgenerator operatively connected to said microprocessor adapted to signalwhether the pre-determined depth is attained.
 15. The medical instrumentaccording to claim 3 wherein said probe extends in a longitudinaldirection, wherein said sensor extends in a elongate, substantiallylongitudinal direction along said outer peripheral surface of said probeand whereby when said probe is inserted into the orifice, said radiationis partially blocked by the walls of the orifice from reaching saidsensor and as said probe is inserted deeper into the orifice even moreof said radiation is blocked by the walls of the orifice from reachingsaid sensor.
 16. A method of determining the depth of insertion of aprobe of a medical instrument into an orifice of a body, comprising: (a)providing a medical instrument including: (1) a support structure; (2) aprobe attached to said support structure, said probe possessing an outerperipheral surface and adapted to be inserted into an orifice in ananimal's body; and (3) a sensor adapted to sense electro-magneticradiation from a source of said radiation remote from the animal's body,said sensor mounted on said outer peripheral surface of said probe in aposition so as to receive said radiation; (b) sensing said radiationfrom said source with said sensor; (c) determining the magnitude of saidradiation sensed by said sensor; (d) inserting said probe into theorifice; (e) monitoring the magnitude of said radiation sensed by saidsensor as said probe is inserted into the orifice; and (f) evaluatingwhether the degree of any reduction of said monitored magnitude as saidprobe is inserted into the orifice indicates the extent to which saidsensor has passed a wall of the orifice.
 17. The method of determiningthe depth of insertion of a probe of a medical instrument into anorifice of a body according to claim 16 further comprising: determiningthe depth of insertion of said probe into the orifice based upon saidevaluation.
 18. The method of determining the depth of insertion of aprobe of a medical instrument into an orifice of a body according toclaim 16 wherein said radiation includes ambient radiation in thevicinity of said medical instrument.
 19. The method of determining thedepth of insertion of a probe of a medical instrument into an orifice ofa body according to claim according to claim 18 wherein said probeextends in a longitudinal direction, wherein said sensor extends in aelongate, substantially longitudinal direction along said outerperipheral surface of said probe and whereby when said probe is insertedinto the orifice, said radiation is partially blocked by the walls ofthe orifice from reaching said sensor and as said probe is inserteddeeper into the orifice even more of said radiation is blocked by thewalls of the orifice from reaching said sensor.
 20. An medicalinstrument including a support structure; a probe attached on saidsupport structure, said probe extending in a longitudinal direction andpossessing an outer peripheral surface and adapted to be inserted intoan orifice in an animal's body; a sensor adapted to senseelectro-magnetic radiation from a source of said radiation remote fromthe animal's body, said radiation including ambient radiation within thevisible spectrum in the vicinity of said medical instrument, said sensormounted on said outer peripheral surface of said probe in a position soas to receive said radiation, wherein said sensor extends in a elongate,substantially longitudinal direction along said outer peripheral surfaceof said probe and whereby when said probe is inserted into the orifice,said radiation is partially blocked by the walls of the orifice fromreaching said sensor and as said probe is inserted deeper into theorifice even more of said radiation is blocked by the walls of theorifice from reaching said sensor; and a microprocessor operativelyconnected to said sensor, said microprocessor configured to monitor themagnitude of said radiation sensed by said sensor and to evaluate thedegree of any reduction of said monitored magnitude as an indication ofthe insertion of said probe into the orifice.